Heat exchange systems are used in various industries for a myriad of applications. Common applications of the heat exchange systems include heating ventilation and air-conditioning (HVAC) installations. In such installations, fluid is circulated through the heat exchange system for heat exchange to occur at a bundle of tubes making up a portion of the heat exchange system. Heat exchange efficiency at the bundle of tubes requires debris and fouling deposits accumulated therewithin to be substantially removed. Taking the heat exchange system off-line for physical flushing is not only ineffective but also disallow use of the heat exchange system for the duration it remains off-line.
Current cleaning systems for use in conjunction with the heat exchange systems uses sponge balls transported by fluid to be fed and circulated in the heat exchange system. When the balls passage through the bundle of tubes during circulation in the heat exchange system, any debris or fouling deposits in the bundle of tubes are pushed out.
It is known in the art that some of such cleaning systems utilize sponge balls that are larger than the internal diameter of the tubes of the heat exchanger. The sponge balls are highly compressible such that when the balls squeeze into the tubes, they tend to expand back to their initial uncompressed state, thereby generating a frictional force along the inner surface of the tube as the balls move through. The sponge balls can thus only be transported singularly through the tube. It is this frictional force along the internal surface of the tubes that scrubs deposits and dirt off the surface. However, if the sponge ball encounters a large deposit, the force of the fluid may not be sufficient to push the sponge ball through and the sponge ball becomes stuck within the tube.
Sponge balls are designed to be used for heat exchanger tubes with smooth internal surfaces. For tubes with rifling grains, also known as enhanced tubes, the scrubbing action of the compressed sponge balls cannot reach the grooves of enhanced tubes; they can only clean the landings of the enhanced tubes. It is in these grooves where dirt accumulates and need cleaning most.
In addition, in heat exchangers with multiple horizontal tubes arranged in stacks, the sponge balls cannot be efficiently distributed to all the tubes in the stacks. The sponge balls are all of the same weight and will generally float or sink to the same portion of the stack. This leaves the other tubes in the stack with little sponge balls to for proper cleaning thereof.
Therefore, there is an apparent need for an improved method of cleaning a heat exchanger in order to address the foregoing problems.